Direct current switching device



y 1933- H. a. TURNER ET AL 1,910,508

DIRECT CURRENT SWITCHING DEVICE Filed Jan. 17, 1931 2 Sheets-Sheet l hz/ezafzzws. fi

' May 23, 1933.

H. i. TURNER ET AL DIRECT CURRENT SWITCHING DEVICE 1 Filed Jan. 17, 1931 2 Sheets-Sheet 2 Patented May 23, 1933 UNITED STATES PAT" OFFICE HARRISON I. TURNER AND ERNEST R. FREEBERG, OF MOLINE, ILLINOIS, ASSIGNORS TO EAGLE SIGNAL SALES CORPORATION, OF MOLINE, ILLINOIS, A CORPORATION OF ILLINOIS DEECT CURRENT SWITCHING DEVICE Application filed January 17, 1931.

The purpose of this invention is to provide a simplified mechanism for performing a plurality of switching operations, and for purposes of illustration the invention is shown embodied in a sign flasher adapted for alternately flashing the lamps in the border or similar design of an electric sign, thereby producing a chasing effect. It will be understood that the invention is not limited to this use, however. An object of the invention is to utilize the intermittent energizing of several circuits for rendering operatlve a series of field magnets, and thereby producing a rotating magnetic field which shall serve to actuate a rotating switch device, said device itself controlling the intermittent magnetization of the several magnets. The invention thus consists in the various features and elements of construction in combination as herein shown and described, and as indicated by the claims.

In the drawings:

Figure 1 is a front elevation of a switching device embodying this invention.

Figure 2 is a side elevation of the same.

Figure 3 is a front elevation of the motor structure as seen by removing the face plate which appears in Figure 1, and with Figure 3 is combined a wirmg diagram indicating the relation of the motor parts to the switching elements which are shown in Figure 1 and omitted from Figure 3.

Figure 4 is a detail elevation of the starting solenoid and ratchet mechanism.

As shown in Figure 1, the mechanism is mounted on a back plate, 1, from which suit able posts, 2, extend forwardly for supporting a face plate, 3, and this face plate supports the switching mechanism. A rotary shaft, 5,

projects through the face plate, 3, and carries a cam disk, 6, having a periphery which is mainly circular, but which has a segment of larger radius than the remainder at 7, said segment serving to actuate successively a plurality of switch devices mounted on the face plate, 3.

' Each of the switch devices comprises a bell crank lever including a bifurcated structure, 8, in which there is journaled a roller, 9, for contact with the cam, 6, and which is carried Serial No. 509,301.

on a fixed fulcrum post or pivot, 10. The connecting web or back of the bifurcated memher, 8, is secured by suitably insuiated fastening means to an angle-shaped member, 11, whose projecting end carries a contact button, 12, and which is connected into one of the electric circuits by a flexible conductor, 13, leading from a binding post, 14, set in the face plate, 3. A fixed contact button, 15, is adjustably mounted on a suitable angle bracket, 16. Thus, as the cam, 6, rotates, its high segment, 7, forces the roller, 9, outwardly and thus swings the lever composed of the parts, 8 and 11, in a direction to separate the contact buttons, 12 and 15. Any number of these contact devices may be disposed at suitable angular intervals around the axis of the shaft, 5, but, as shown, there are four of them placed 90 degrees apart, so that with each quarter revolution of the shaft, 5, one of the circuits is opened and held open for a period corresponding to the angular extent of the cam segment, 7.

As shown, the cam segment is substantially 90 in extent, so that for a brief interval it holds two successive contacts open simultaneously, and then continues to hold one of them open alone after the other is closed. Where a series ofv lamps are arranged in sequence, as in the border of an electric sign, and particularly where they are disposed in a serpentine design, this operation of the switching contacts gives the desired chaser effect in the successive lighting and dimming of the lamps. Somewhat different effects may obviously be secured by changing the extent of the cam segment, 7, or providing a plurality of such segments and a different number of contact devices.

To reduce the arcing of the contact devices, particularly when a considerable number of lamps are connected in parallel with each contact, we provide condensers, 17, each connected across the gap of one of said contact mechanisms in accordance with well understood principles. These condensers are shown mounted on the back plate, 1, below the rotary mechanism.

For causing rotation of the shaft, 5, and its cam member, 6, the shaft carries an armature, 18, of magnetic material, preferably iron, and a series of field magnets, 19, shown as four in number, are disposed at equal angular intervals about the axis of the shaft, 5. These electromagnets have their coils connected to the same source of energy which 1i hts the lamps, and through the same series 0? switch devices which control the lamps, as above described. The armature, 18, is designed to rotate in the direction of the arrow, 20, shown thereon in Figure 3, and is formed with a horn or projection, 21, at its leading side, which permits the magnetic pull of any one of the field magnets to secure an initial drag for shifting the armature out of registration with the last preceding field magnet. The unsymmetrical form of the armature is balanced for rotation by a counter-weight, 22, preferably of non-magnetic material. Thus, as the field coils, 19, are successively energized in sequence corresponding to their position around the axis of the shaft, 5, the armature, 18, is caused to rotate in response to the rotating magnetic field. It is not necessary that any large amount of power be developed, since the only work which the device does is the opening of the yielding contact devices by means of the cam se ment, 7.

or initiating the rotation of the shaft, 5, whenever the main circuit is closed we provide a solenoid, 23, whose plunger is connected to reciprocate a bar, 24, carrying a pivoted ratchet dog, 25. A spring, 26, normally holds the bar, 24, at the upper end of its stroke until the solenoid, 23, is energized, and when this occurs the bar, 24, is pulled strongly downward, causing the dog, 25, to engage the ratchet wheel, 27, on the shaft, 5, and thus rotate the shaft and its armature, 18, throu h a part of a turn at least. Momentum won (1 probably carry the armature through several revolutions, but in any event it would be picked up within a quarter turn by the pull of the electromagnets, 19, and from that time its rotation will continue until the main current supply is shut off. The solenoid, 23, is preferably arranged to remain in the circuit holding the bar, 24, at its lower limit with the spring, 26, com ressed, said spring being relatively light, smce its only duty is to return the bar, 24, to its upper limit. The spring, 28, associated with the dog, 25, holds the do yieldingly in position for engagement witfi the teeth of the ratchet wheel, but permits it to be deflected during the upward movement of the bar, 24.

For controllin the speed at which this ty e of motor W111 operate, and to insure a fairly uniform speed a simple form of magnetic brake may be employed comprising a metallic disc, 30, which is fast on the shaft, 5, and rotates between the poles of a permanent magnet, 31. Said magnet is adjustably mounted on a pivot axis at 32 so that as it magnet, A, is in this circuit.

is swung about this axis its oles may be made to overlap the surface 0 the disc, 30. 4

more or less, thus varying the drag or brakin effect which the magnet produces. An in icator or pointer arm, 33, rigidly connected with the magnet, may be arranged to swing over a graduated scale, 34, throughout the range of adjustment, and may also serve as a handle for shifting the magnet.

An illustrative circu1t is indicated in Figure 3 in conjunction with the showing of the armature and field magnets. The respective magnets are marked A, B, C and D, and the corresponding circuit breakers are similarly indicated in the diagram at the lower part of the sheet. There are four se arate light circuits leading into the machine at binding posts numbered I, II, III and IV, shown on Figure 1 and similarly indicated on the wiring diagram of Figure 3. The lights themselves are indicated by letters a, b, c and d. The lights, a, are in circuit I, controlled by circuit breaker, A, and field In most installations these lights are arranged in one or more rows around the border of an electric sign; and if there are four circuits, as shown in the present instance, each of the lights, a, will be extinguished simultaneously, and then will flash on again whilethe lights, I), are extinguished. The dark spots thus shifting along through the series in multiple arrangement seem to be chasing each other around the border, from which the apparatus is commonly known as a sign chaser. In the example illustrated the source of current is indicated as an ordinary two-wire system entering the chaser by way of leads L and L.

We claim:

1. In combination, an armature mounted for rotation about an axis, and a plurality of field coils disposed symmetrically about said axis, a plurality of outside circuits con- I nected respectively to said field coils, a source of electrical energy connected to each of said field coils and to each of said circuits, and common switching means for said coils and circuits, and actuated by the rotation of the armature arranged to open said circuits successively in the order of arran ement of the coils about said axis, thus slmultaneously de-energizing the field coils in the same order, and causing rotation of the armature by rotatively shifting the field which attracts said armature.

2. In the combination defined in claim 1, each of the field coils being connected in parallel with one of the outside circuits.

3. In combination, an armature mounted for rotation about an axis, a plurality of electromagnets disposed symmetrically about said axis, a plurality of outside circuits connected respectively to said electromagnets, a source of electrical energy connected to each of said magnets and to each of said circuits, a set of normally closed yieldable circuit breakers, one for each of said circuits, and each also connected for controlling one of the electromagnets, said circuit breakers bealso disposed symmetrically about the axls of rotation of the armature, and mechanical means associated with the armature for actuating said circuit breakers successively as the armature rotates for momentarily opening the circuits in succession, and simultaneously producing rotation of the field set up by the electromagnets by opening the electromagnet circuits successively. 4. In combination with an electric lighted display device comprising lamps arranged in a row and in a lurality of parallel circuits means for fias g or extinguishing said lamps in the order of their arrangement comprising a series of switching devices, one for each circuit, arranged around an axis in an order corresponding to that of the lamps, an armature mounted for rotation about said axis, with a plurality of field coils disposed about said axis, a source of electrical energy with which each of the parallel lamp circuits may be connected, said field coils being included respectively in said lamp circuits, and said armature-being connected for actuating the switching means as it rotates, whereby the separate switchin means for each circuit also energizes the eld coils in succession, thus producing a rotation of the magnetic field about the axis of said armature and maintaining said rotation.

5A In the combination defined in claim 4,

the armature having a cam member, the switching means consisting of circuit breakers positioned, for successive actuation by said cam member rotating with the armature,

and said cam being of 'suflicient angular extent to keep one of said circuit breakers open during-the openin of the next succeeding circuit reaker of t e series, but permit. ting closing of the first mentioned circuit breaker during a rtion of the interval for which the secon circuit breaker remains pe HARRISON I. TURNER. ERNEST R. FREEBERG, 

